YOUK, YUCK! Kevin Youkilis, 1-for-4 on Monday, was one of the new Yankees who did not impress in the opener. Photo: Anthony J Causi

YOUK, YUCK! Kevin Youkilis, 1-for-4 on Monday, was one of the new Yankees who did not impress in the opener. (
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Reality began setting in for the Yankees on Monday — if it hadn’t before — when they rolled out their new lineup against the Red Sox and watched it come up empty against Jon Lester.

“It was just one game,” Lyle Overbay said after the loss. “You can’t get worried over one loss.”

Sure you can.

Since Boston used relievers from both sides in the 8-2 win in The Bronx, the Yankees got a look at more than a few of their recently signed players — many of whom were discarded by other organizations.

Kevin Youkilis, Vernon Wells and Ben Francisco started against Lester, a southpaw, while Overbay and Travis Hafner pinch-hit and stayed in the game.

None of them was particularly impressive.

And though it was just the first game of the season, as Overbay pointed out, most of the players who made their debuts Monday struggled throughout the spring.

Tonight, with righty Clay Buchholz scheduled to start for Boston, Yankees manager Joe Girardi could stock his lineup with lefties, including Brennan Boesch, as well as holdovers like Brett Gardner, Ichiro Suzuki and Robinson Cano.

“These are all veteran guys,” Youkilis said. “It’s not like none of these players have proven themselves in the past.”

But it is far from the offense that the Yankees are accustomed to putting on the field. And unless better options become available, former castoffs like Francisco, Boesch and Overbay — who were all cut loose this spring — likely will be relied upon as the Yankees wait for familiar faces Mark Teixeira, Curtis Granderson and Derek Jeter to return.

“We have guys in there who have been in this game for a long time, guys who know how to play the game,” Cano said yesterday. “We have to stay in the race for whenever we get those guys back.”

Cano figures to be able to do his part, but he can’t do it alone.

One scout who watched the Yankees on Monday said he was among those not shocked by the Yankees’ failure to produce.

“A lot of the guys they picked up were let go by teams that know what they’re doing and have money,” he said. “It’s not like they’re capitalizing on other people’s mistakes. They’ll just have to get lucky.”

For one day, that luck did not materialize. And in an AL East that could shape up to be very tough, the Yankees can ill afford to get off to a slow start until their stars get back on the field.